Life consists with Wildness. The most alive is the wildest. Not yet subdued to man, its presence refreshes him. One who pressed forward incessantly and never rested from his labors, who grew fast and made infinite demands on life, would always find himself in a new country or wilderness, and surrounded by the raw material of life. He would be climbing over the prostrate stems of primitive forest trees.

Certainly, we do not need to be soothed and entertained always like children. He who resorts to the easy novel, because he is languid, does no better than if he took a nap.

Mathematics should be mixed not only with physics but with ethics.

Thank God, they cannot cut down the clouds!

You will pardon some obscurities, for there are more secrets in my trade than in most men's, and yet not voluntarily kept, but inseparable from its very nature. I would gladly tell all that I know about it, and never paint "No Admittance" on my gate.

If the day and night are such that you greet them with joy, and life emits a fragrance like flowers and sweet-scented herbs, is more elastic, more starry, more immortal - that is your success.

Simplicity is the law of nature for men as well as for flowers.